EM1 Product Description The EM1 is a transmissive optical encoder module designed to measure rotary or linear motion when paired together with an encoder disk or linear strip. The EM1 consists of a lensed LED source and a monolithic detector IC enclosed in a small polymer package. The EM1 uses phased array detector technology, allowing for a wider gap tolerance and reliable performance even with some disk contamination.
The EM1 encoder module provides digital A & B quadrature outputs with an optional index channel. Each EM1 module is resolution-specific and is matched to the resolution of an encoder disk or linear strip. The EM1 module supports 21 different resolutions. The EM1 operates with a single 5V supply and provides single-ended outputs capable of sinking and sourcing 8mA. An internal 0.1 µF decoupling capacitor provides enhanced noise immunity.
For open collector and higher voltage applications, add the PC3 cable driver, or for differential cable driver outputs, add the PC4 cable driver.
Accessories such as encoder disks, linear strips, mating connectors and cables are also available.
Product Specifications
COMPATIBLE 1" & 2" DISKS
1" DISKS
CPR
MODULE
1" DISK
MODULE
1" DISK
32
EM1-1-32-N
DISK-1-32-*-NE
50
EM1-1-50-N
DISK-1-50-*-NE
EM1-1-50-I
DISK-1-50-*-IE
96
EM1-1-100-N
DISK-1-96-*-NE
EM1-1-100-I
DISK-1-96-*-IE
100
EM1-1-100-N
DISK-1-100-*-NE
EM1-1-100-I
DISK-1-100-*-IE
120
EM1-1-100-N
DISK-1-120-*-NE
192
EM1-1-200-N
DISK-1-192-*-NE
EM1-1-200-I
DISK-1-192-*-IE
200
EM1-1-200-N
DISK-1-200-*-NE
EM1-1-200-I
DISK-1-200-*-IE
250
EM1-1-250-N
DISK-1-250-*-NE
EM1-1-250-I
DISK-1-250-*-IE
256
EM1-1-250-N
DISK-1-256-*-NE
EM1-1-250-I
DISK-1-256-*-IE
360
EM1-1-360-N
DISK-1-360-*-NE
EM1-1-360-I
DISK-1-360-*-IE
400
EM1-1-400-N
DISK-1-400-*-NE
EM1-1-400-I
DISK-1-400-*-IE
500
EM1-1-500-N
DISK-1-500-*-NE
EM1-1-500-I
DISK-1-500-*-IE
512
EM1-1-512-N
DISK-1-512-*-NE
EM1-1-512-I
DISK-1-512-*-IE
540
EM1-1-540-N
DISK-1-540-*-NE
EM1-1-540-I
DISK-1-540-*-IE
720
EM1-1-720-N
DISK-1-720-*-NE
EM1-1-720-I
DISK-1-720-*-IE
800
EM1-1-800-N
DISK-1-800-*-NE
EM1-1-800-I
DISK-1-800-*-IE
1000
EM1-1-1000-N
DISK-1-1000-*-NE
EM1-1-1000-I
DISK-1-1000-*-IE
1024
EM1-1-1024-N
DISK-1-1024-*-NE
EM1-1-1024-I
DISK-1-1024-*-IE
1250
EM1-1-1250-N
DISK-1-1250-*-NE
EM1-1-1250-I
DISK-1-1250-*-IE
*Represents the bore size
2" DISKS
CPR
MODULE
2" DISK
MODULE
2" DISK
64
EM1-1-32-N
DISK-2-64-*-NE
100
EM1-1-50-N
DISK-2-100-*-NE
EM1-1-50-I
DISK-2-100-*-IE
200
EM1-1-100-N
DISK-2-200-*-NE
EM1-1-100-I
DISK-2-200-*-IE
400
EM1-1-200-N
DISK-2-400-*-NE
EM1-1-200-I
DISK-2-400-*-IE
500
EM1-2-500-N
DISK-2-500-*-NE
EM1-2-500-I
DISK-2-500-*-IE
512
EM1-2-500-N
DISK-2-512-*-NE
EM1-2-500-I
DISK-2-512-*-IE
800
EM1-1-400-N
DISK-2-800-*-NE
EM1-1-400-I
DISK-2-800-*-IE
1000
EM1-2-1000-N
DISK-2-1000-*-NE
EM1-2-1000-I
DISK-2-1000-*-IE
1024
EM1-2-1024-N
DISK-2-1024-*-NE
EM1-2-1024-I
DISK-2-1024-*-IE
1800
EM1-2-1800-N
DISK-2-1800-*-NE
EM1-2-1800-I
DISK-2-1800-*-IE
2000
EM1-2-2000-N
DISK-2-2000-*-NE
EM1-2-2000-I
DISK-2-2000-*-IE
2048
EM1-2-2048-N
DISK-2-2048-*-NE
EM1-2-2048-I
DISK-2-2048-*-IE
2500
EM1-2-2500-N
DISK-2-2500-*-NE
EM1-2-2500-I
DISK-2-2500-*-IE
*Represents the bore size
COMPATIBLE 1" & 2" HUBDISKS
1" HUBDISKS
CPR
MODULE
1" HUBDISK
MODULE
1" HUBDISK
32
EM1-1-32-N
HUBDISK-1-32-*-NE
50
EM1-1-50-N
HUBDISK-1-50-*-NE
EM1-1-50-I
HUBDISK-1-50-*-IE
96
EM1-1-100-N
HUBDISK-1-96-*-NE
EM1-1-100-I
HUBDISK-1-96-*-IE
100
EM1-1-100-N
HUBDISK-1-100-*-NE
EM1-1-100-I
HUBDISK-1-100-*-IE
120
EM1-1-100-N
HUBDISK-1-120-*-NE
192
EM1-1-200-N
HUBDISK-1-192-*-NE
EM1-1-200-I
HUBDISK-1-192-*-IE
200
EM1-1-200-N
HUBDISK-1-200-*-NE
EM1-1-200-I
HUBDISK-1-200-*-IE
250
EM1-1-250-N
HUBDISK-1-250-*-NE
EM1-1-250-I
HUBDISK-1-250-*-IE
256
EM1-1-250-N
HUBDISK-1-256-*-NE
EM1-1-250-I
HUBDISK-1-256-*-IE
360
EM1-1-360-N
HUBDISK-1-360-*-NE
EM1-1-360-I
HUBDISK-1-360-*-IE
400
EM1-1-400-N
HUBDISK-1-400-*-NE
EM1-1-400-I
HUBDISK-1-400-*-IE
500
EM1-1-500-N
HUBDISK-1-500-*-NE
EM1-1-500-I
HUBDISK-1-500-*-IE
512
EM1-1-512-N
HUBDISK-1-512-*-NE
EM1-1-512-I
HUBDISK-1-512-*-IE
540
EM1-1-540-N
HUBDISK-1-540-*-NE
EM1-1-540-I
HUBDISK-1-540-*-IE
720
EM1-1-720-N
HUBDISK-1-720-*-NE
EM1-1-720-I
HUBDISK-1-720-*-IE
800
EM1-1-800-N
HUBDISK-1-800-*-NE
EM1-1-800-I
HUBDISK-1-800-*-IE
1000
EM1-1-1000-N
HUBDISK-1-1000-*-NE
EM1-1-1000-I
HUBDISK-1-1000-*-IE
1024
EM1-1-1024-N
HUBDISK-1-1024-*-NE
EM1-1-1024-I
HUBDISK-1-1024-*-IE
1250
EM1-1-1250-N
HUBDISK-1-1250-*-NE
EM1-1-1250-I
HUBDISK-1-1250-*-IE
*Represents the bore size
2" HUBDISKS
CPR
MODULE
2" HUBDISK
MODULE
2" HUBDISK
64
EM1-1-32-N
HUBDISK-2-64-*-NE
100
EM1-1-50-N
HUBDISK-2-100-*-NE
EM1-1-50-I
HUBDISK-2-100-*-IE
200
EM1-1-100-N
HUBDISK-2-200-*-NE
EM1-1-100-I
HUBDISK-2-200-*-IE
400
EM1-1-200-N
HUBDISK-2-400-*-NE
EM1-1-200-I
HUBDISK-2-400-*-IE
500
EM1-2-500-N
HUBDISK-2-500-*-NE
EM1-2-500-I
HUBDISK-2-500-*-IE
512
EM1-2-500-N
HUBDISK-2-512-*-NE
EM1-2-500-I
HUBDISK-2-512-*-IE
800
EM1-1-400-N
HUBDISK-2-800-*-NE
EM1-1-400-I
HUBDISK-2-800-*-IE
1000
EM1-2-1000-N
HUBDISK-2-1000-*-NE
EM1-2-1000-I
HUBDISK-2-1000-*-IE
1024
EM1-2-1024-N
HUBDISK-2-1024-*-NE
EM1-2-1024-I
HUBDISK-2-1024-*-IE
1800
EM1-2-1800-N
HUBDISK-2-1800-*-NE
EM1-2-1800-I
HUBDISK-2-1800-*-IE
2000
EM1-2-2000-N
HUBDISK-2-2000-*-NE
EM1-2-2000-I
HUBDISK-2-2000-*-IE
2048
EM1-2-2048-N
HUBDISK-2-2048-*-NE
EM1-2-2048-I
HUBDISK-2-2048-*-IE
2500
EM1-2-2500-N
HUBDISK-2-2500-*-NE
EM1-2-2500-I
HUBDISK-2-2500-*-IE
*Represents the bore size
COMPATIBLE LINEAR STRIPS
LPI
MODULE
Linear Strip
MODULE
Linear Strip
120
EM1-0-120-N
LIN-120-*-N
EM1-0-120-I
LIN-120-*-#
125
EM1-0-127-N
LIN-125-*-N
EM1-0-127-I
LIN-125-*-#
127
EM1-0-127-N
LIN-127-*-N
EM1-0-127-I
LIN-127-*-#
150
EM1-0-150-N
LIN-150-*-N
EM1-0-150-I
LIN-150-*-#
180
EM1-0-180-N
LIN-180-*-N
EM1-0-180-I
LIN-180-*-#
200
EM1-0-200-N
LIN-200-*-N
EM1-0-200-I
LIN-200-*-#
250
EM1-0-250-N
LIN-250-*-N
EM1-0-250-I
LIN-250-*-#
360
EM1-0-360-N
LIN-360-*-N
EM1-0-360-I
LIN-360-*-#
500
EM1-0-500-N
LIN-500-*-N
EM1-0-500-I
LIN-500-*-#
* Represents length of Linear Strip
* Represents length of Linear Strip
ENVIRONMENTAL
Parameter
Value
Units
Operating Temperature
-40 to 100
C
Electrostatic Discharge, IEC 61000-4-2
± 4
kV
Vibration (10Hz to 2kHz, sinusoidal)
20
G
Shock (6 milliseconds, half-sine)
75
G
OPERATING CONDITIONS
PARAMETER
MIN.
MAX.
UNITS
A/B Output Frequency
0
300
kHz
Disk RPM
0
(18 x 10^6) / CPR
RPM
Linear Strip Speed
0
(3 x 10^5) / LPI
inches/sec.
Disk/Linear Strip Radial Position Tolerance
±.005
inch
ELECTRICAL SPECIFICATIONS
Specifications apply over the entire operating temperature range.
Typical values are specified at Vcc = 5.0V and 25C.
PARAMETER
MIN.
TYP.
MAX.
UNITS
CONDITIONS
Supply Voltage
4.5
5.0
5.5
V
Ripple < 100 mVpp
Supply Current, EM1-0- (linear strip)
27
33
mA
LPI < 250, no load
Supply Current, EM1-1- (1" disk)
27
33
mA
CPR < 500, no load
Supply Current, EM1-2- (2" disk)
27
33
mA
CPR < 1000, no load
Low-level Output
0.5
V
IOL = 8mA max.
High-level Output
2.0
V
IOH = -8mA max.
Output Current Per Channel
-8
8
mA
Load Capacitance
100
pF
Output Rise Time
110
nS
Output Fall Time
100
nS
TIMING CHARACTERISTICS
ENCODING CHARACTERISTICS:
Specifications apply over the entire operating temperature range.
Values are for the worst error over full rotation.
Refer to the timing diagram below.
PARAMETER
SYMBOL
MIN.
TYP.
MAX.
UNITS
Symmetry
X, Y
150
180
210
°e
Quadrature
Z
60
90
120
°e
Index Pulse Width
Po
40
90
120
°e
Ch. I Rise After Ch. B or Ch. A Fall
t1
50
100
200
ns
Ch. I Fall After Ch. B or Ch. A Rise
t2
-10
15
25
ns
TIMING DIAGRAM:
CPR: The number of Cycles (C) of the A or B outputs Per Revolution.
Cycle Error: An indication of cycle uniformity. The difference between an observed shaft angle which gives rise to one electrical cycle, and the nominal angular increment of 1/CPR of a revolution.
Index (I): The index output goes high once per revolution, coincident with the low states of channels A and B, nominally 1/4 of one cycle (90 ° e).
LPI : Lines Per Inch. The number of Cycles (C) of the A or B output per inch of linear strip movement.
One Shaft Rotation: 360 mechanical degrees.One Electrical Degree (°e): 1/360th of one cycle.One Cycle (C): 360 electrical degrees (° e). Each cycle can be decoded into 1 or 4 states, referred to as X1 or X4 resolution multiplication.
PPR : The number of resolvable Positions Per Revolution of the encoder disk with x4 quadrature decoding.
Quadrature (Z): The phase lag or lead between channels A and B in electrical degrees, nominally 90 ° e.
Symmetry: A measure of the relationship between (X) and (Y) in electrical degrees, nominally 180° e.
EM1 / HEDS COMPARISON
US Digital is the designer and manufacturer of the EM1 transmissive optical encoder module. The design of the EM1 provides electrical and mechanical compatibility with HEDS-9000 , HEDS-9100 , HEDS-9200 , HEDS-9040 , and HEDS-9140 series modules.
The process of switching from the HEDS to the EM1 module should not require any mechanical or electrical changes. Simply use the EM1 and matching codewheel in place of the HEDS module and codewheel. The EM1 has a built-in index channel available on most resolutions, for both rotary disks and linear strips. The EM1 uses a US Digital designed codewheel with 2 tracks rather than 3 tracks for index versions. The EM1 offers improved output drive capability and will source and sink 8mA at TTL levels.
Physically, the EM1 has no external wire loops which can interfere when mounting. The connector pins are 0.051" shorter than HEDS modules, while still providing .30" insertion depth. US Digital's EM1 offers custom resolutions.
PIN-OUTS
Pin
Description
1
Ground
2
Index
3
A channel
4
+5VDC power
5
B channel
PRODUCT CHANGE NOTIFICATIONS
Title
Date
Description
Download
EM1 LED Die - PCN 1016
2/7/2013
As part of US Digital's continual assurance of supply strategy, we have qualified additional sources for our LED die used in our EM1 encoder module, which in turn impacts all of the following products:
Download
EM1 & EM2 Update - PCN 4199
1/14/2014
Based on our continuous process improvement program, US Digital is changing the current marking method for our EM1 and EM2 encoder modules to a serialization method. This change will allow for each module to have a unique code; the current marking method is based on a date code system that includes all encoder modules produced within a specific week / year. The serialization system will be based on a hexadecimal system.
Download
Additional Information
Product Notes
US Digital® warrants its products against defects in materials and workmanship for two years. See complete warranty for details.
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